Pipe thread protector



M rch 1 ,-1932- c. J. HOCHENAUER ETAL 1,847,396

PIPE THREAD PROTECTOR Filed Sept. 30. 1927 IN VEN TORS By A/YD Camus S. 5/7/77/ bcu A TTORNEYS Patented Mar. 1, 1932 UNITED STATES PATENT OFFICE CARL J. HOCHENAUER AND CHARLES S. SMITH, OF MILWAUKEE, WISCONSIN, ASSIGNORS TO A. 0. SMITH CORPORATION, OF MILWAUKEE, WISGONSIN, A CORPORATION OF NEW YORK PIPE THREAD PROTECTOR.

Application filed September 30, 1927. Serial No. 222,962.

The present invention relates to devices for protecting lengths of pipe against damage to the threaded ends thereof.

The invention'resides in a new construce tion of thread protector drawn from sheet metal into the form of a cap or shell, open at one end and closed at the other. The metal at the bottom of the cap or shell is pressed inwardly so as to form a construction having a conical formation in cross-section,

such formation being positioned concentrically with reference to the side walls of the cap or shell, and being adapted to be entered into the open end of the pipe, so as to maintain theprotector clear of the crest of the threads on the end of the pipe.

The inside diameter of the thread protector will conform to the diameter of standard pipe, so that when the protector is slipped ll over the threaded end of a len h of pipe, the margin at the inner or top e ge of the protectorwill closely embrace an unthreaded section of the pipe next to the threaded end thereof, and so make a tight joint at that 5 point, which will efiectively exclude moisture, dirt and other deleterious substance, which would affect the threads adversely. V

The side walls of the thread protector stand parallel or approximately parallel, and clear 0 of the crest of the threads. The conical formation before referred to has the function of maintaining the thread protector in that position.

In combination with the above'construction, we have included a novel means for securing the thread protector in position upon the end of a pipe, such means consisting of soft metal plugs which are driven through perforations in the wall of the thread protector, and into engagement with the underlying threads on the end of the pipe. The soft metal plugs readily adapt themselves to the contour of the threads on the pipe, and so constitute complemental threads in the thread protector, to retain the protector firmly in position, and insure the handling of-the pipe thus protected without damage to the threads, but permitting the easy removal of the thread protector from the pipe by simply unscrewing.

Having thus outlined the nature and purposes of our invention, the same will be now specifically described, and the novelty thereof pointed out in the appended claims.

In the accompanying drawing, the illustration is a vertical sectional view through one end of a length of pipe, showing tapering threads at its extreme end, and showing the formation of our improved thread protector and the manner in which it is secured in position upon the end of the length of pipe.

In the drawing, the numeral 10 indicates the end section of a length ofpipe of any standard diameter. The pipe illustrated is shown as provided with a tapering thread at its end. a

The pipe protector is indicated by the numeral 11. It comprises a cap or shell having an inner or open end 12, and a closed bottom 13 inset from the other or outer end of the cap. The axial dimensions of the thread protector are somewhat greater than the length of the threaded section of the pipe, so that when the protector is applied to the pipe by slipping it .thereover, the threaded end is completely enclosed, and the rim 12 of the-protector will snugly embrace an unthreaded section. of the pipe lying next to the threaded end thereof, so as to make a reasonably tight joint at that point, which will to a very great extent exclude water, dirt and other substances, which would cause injury to the threads of the pipe.

In formingthe thread protector, it is preferable to employ a disc of sheet metal, the marginof which for a width sufficient to form the parallel side walls, is drawn vertically. Thenumeral 14 designates the portion of the metal disc remaining in its original plane, and which, in the completed article stands transversely to the axis of the thread protect-or. As before stated, the numeral 13 indicates the inset bottom of the thread protector, the parts 13 and 14 being connected by a tapering concentric wall 15,

forming with the inset bottom 13 a truncated cone.

The conical formation is adapted, when the thread protector is applied to the end of the pipe, to enter the open end of the letter,

and be seated firmly against the angle thereof, the line of contact being shown in the drawing. We propose generally that the outer walls of the thread protector shall be parallel or substantially parallel, so as to have little or no contact with the threads of the pipe, especially at the outer end thereof, where the crest of the threads is sharply defined. Such an arrangement provides a clearance between the thread protector and the threads of the pipe, and this clearance is maintained by reason of the entry of the conical formation into the open end of the pipe. As a result, impact of a blow struck upon the thread protector at one side of the pipe will not reach the threads but will be resisted by the cone and be transmitted to the opposite side of the pipe.

The thread protector is positioned by being slipped over the end of the pipe as shown, and is maintained in fixed position thereon for the purposes of the invention, by driving soft metal plugs 16 through openings in the P parallel walls of the pipe, which openings may be flared outwardly as at 17. The soft metal plugs 16 readily adapt themselves to the contour of the threads on the pipe, and

by spreading into the space between the threads and the thread protector are securely anchored against accidental displacement.

As before indicated, the soft metal plugs 16, when engaged with the threads of the pipe in the manner described, constitute complemental threads in the thread protector. When it is desired to remove the thread protector, it can be eflfected by simply unscrewing the latter, and the pipe is ready for use.

The soft metal plugs may be easily removed from the thread protector by simply punching them out, after which the thread protector will be ready for re-use without waste or any other attention.

Our improved thread protectors are adapted touse in connection with standard pipe of different wall thicknesses. In thin walled pipe, the end of such pipe will enter more fully into the annular recess formed by the conical formation 15 and the outer walls of the thread protector, while in the case of thick walled pipe the entry will not be as far.

Having thus described our invention, what we claim and desire to secure by Letters Patent of the United States, is

1. A pipe thread protector having a cylin:

drical side wall portion and an end wall integral therewith, the major portion of said end wall being inset from and closely adjacent the outer end of the protector, a transverse wall portion at the end of the protector, an inclined wall portion connecting said inset portion to the transverse wall for maintaining the cylindrical side wall portion in spaced relation to the threaded portion of a pipe when said protector is placed over the end thereof, said side wall portion being provided with openings and soft metal plugs adapted to be inserted through said openings and into engagement with the threads of the pipe for detachably securing the protector in position upon the pipe.

2. A protector for the threaded ends of pipe comprising a sleeve for covering the threaded end of a pipe, the sleeve being provided with perforations, an end provided in the sleeve or closing the end of the pipe, a support for the sleeve formed from the end, the support simulating a truncated cone and extending inwardly to facilitate insertion into i pipes of different wall thicknesses, the wall of the support being adapted to engage the inner edge of the end of the pipe to support the sleeve, and soft metal plugs for mount ing in the perforations in the sleeve to retain the protector in position.

3. A protector for the threaded ends of ipe comprising a sleeve for covering the threaded end of a pipe, the sleeve being provided with perforations, a closure at one end of the sleeve, means for supporting and centering the sleevewithin pipes of different wall thicknesses, comprising an inturned portion of the sleeve shaped to simulate a truncated cone and adapted to engage the inner edge of the end of the pipe, and soft metal plugs mounted in the perforations in the sleeve to retain the protector in positionon the pipe.

In testimony whereof, we have signed our names at Milwaukee, this 28th day of September, 1927.

C. J. HOGI-IENAUER. C. S. SMITH. 

